JPS627554Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a monitoring window that is attached to instruments such as a gas monitoring unit of a car cooler or a water meter, and its purpose is to improve the transparency of the window glass.

Generally, a monitoring window for monitoring the condition inside an airtight container from the outside is equipped with a Fe
It has a structure in which a transparent window glass 2 is welded to the inner peripheral surface 1a of a metal ring 1. Incidentally, the metal ring 1 has, for example, four mounting holes 3 drilled therein, and an O-ring fitting groove 4 surrounding the window glass 2 is formed on the inner surface 1b.
An O-ring 5 is fitted into this groove 4. Then, the metal ring 1 is tightened to the tank wall 7 by inserting the bolt 6 into the mounting hole 3, and the O-ring 5 fitted in the groove 4 is pressed onto the area around the window hole 8 of the tank wall 7 to close the monitoring window on the tank. It is installed airtight.

Welding of the window glass 2 of such a monitoring window is performed by the third
This is carried out using a sealing jig 9 made of graphite as shown in the figure. That is, the upper surface of the sealing jig 9 is formed with a convex portion 10 having a flat upper surface that fits into the inner circumferential surface 1a of the metal ring 1 by a certain height d.
0, and position and place the metal ring 1 on the sealing jig 9. Next, a transparent glass disk 11 is placed on the convex portion 10 in the metal ring 1,
The whole is heated to a high temperature of about 1000° C. in a neutral or slightly reducing atmosphere to melt the glass disk 11. Then, this molten glass is welded to the inner circumferential surface 1a of the metal ring 1, as shown in FIG. 4, and a transparent window glass 2 is formed. At this time, the inner surface 2a of the window glass 2 is formed to be spaced apart from the inner surface 1b of the metal ring 1 by the height d of the convex portion 10 of the sealing jig 9, thereby allowing the monitoring window to be placed on the inner surface of the desk or the like. When placed with 2a facing down, this inner surface 2a is prevented from coming into direct contact with the desk, and the inner surface 2a is protected from being scratched and the window glass 2 from being broken. Further, the inner surface 2a of the window glass 2 is formed flat on the flat upper surface of the convex portion 10. Further, the outer surface 2b of the window glass 2 has its peripheral edge rising along the inner peripheral surface 1a of the metal ring 1,
It is formed as a curved smooth free surface.

By the way, the inner surface 2a of the window glass 2 is sealed with a sealing jig 9.
Since this is a so-called jig contact surface formed by the upper surface of the convex portion 10, the following problem occurred. That is, the sealing jig 9 is generally formed by grinding, and therefore, even if the upper surface of the convex portion 10 is flat overall, microscopically it is an uneven surface. Therefore, the inner surface 2a of the window glass 2 did not have a smooth surface, but had small unevenness like ground glass, which deteriorated the transparency of the window glass 2. In order to increase the transparency of the window glass 2, the upper surface of the convex portion 10 is smoothed and the inner surface 2 is smoothed.
It is conceivable to make a a smooth surface, but the convex portion 10
If the upper surface of the window glass 2 is made smooth, the molten glass will adhere to the upper surface of the convex portion and will not separate when the window glass 2 is formed by welding, which is impractical.

Therefore, the inner surface 2 of the window glass 2, which is the surface that touches the jig,
It is conceivable to improve the transparency of the window glass 2 by applying a transparent resin such as silicone resin to a.

FIG. 5 shows that the inner surface 2a of the window glass 2 welded to the metal ring 1 in the conventional manner is made of a transparent resin 12 such as silicone resin.
An example of applying a thin layer of In this way, transparent resin 1
When 2 is applied in a thin film form to the inner surface 2a, the inner surface 2 is coated as if the uneven surface of ground glass was wetted with water.
The unevenness of the window glass 2a is smoothed by the transparent resin 12, thereby eliminating diffuse reflection of light on the inner surface 2a and increasing the transparency of the window glass 2. Although the transparent resin 12 is applied to at least the central portion of the inner surface 2a, it may be applied to the entire surface.

However, since the transparent resin 12 is a soft film such as silicone resin, there is a problem that the transparency of the window glass 2 is easily reduced due to scratches during transportation or handling.

In view of the above-mentioned problems, the present invention has been developed to improve and eliminate these problems.The present invention has been developed to improve and eliminate the above-mentioned problems. A transparent adhesive is applied to fill the window glass, and a transparent plate having a hardness greater than the hardness of the transparent adhesive after curing is bonded through the transparent adhesive to increase the transparency of the window glass. To provide a monitoring window that does not easily deteriorate.

For example, when applied to the above-mentioned surveillance window, the present invention can be applied to the inner surface of the window glass 2, as shown in FIG.
A transparent plate 14 is adhered to a part or the entire surface of a through a transparent adhesive 13 such as silicone resin. The transparent plate 14 is made of a hard material such as glass or resin and has a smooth surface. With this structure, the inner surface 2a of the window glass 2 is coated with the transparent adhesive 13.
The transparency of the window glass 2 is increased by smoothing it, and the transparent adhesive 13 is protected by a transparent plate 14.
High transparency can be maintained for a long period of time.

Note that the above embodiment uses the O-ring 5 and the bolt 6.
Although the case where the metal ring 1 is fixed to the tank wall 7 has been described, for example, as shown in FIG.
It can also be applied to a structure in which it is fixed to the peripheral corner of the window hole 8 of the tank wall 7 by welding.

As explained above, according to the present invention, the transparency of the window glass of the monitoring window is further improved by adhesion of the transparent plate through the transparent adhesive material, which not only makes it easier to monitor the oil level of the fuel tank, etc. Since the transparent adhesive is protected by a transparent plate, it is possible to maintain high transparency for a long period of time compared to a case where a transparent resin is simply applied. In addition, since it is only necessary to adhere the transparent plate to the window glass of the monitoring window using a transparent adhesive, the conventional monitoring window can be used as is, which has great practical value.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventional monitoring window when installed;
The figure is a front view seen from the left of Figure 1, Figures 3 and 4.
The figures are cross-sectional views at each step to explain the manufacturing method of the monitoring window, Figure 5 is a cross-sectional view showing the monitoring window that is the background of the present invention, and Figure 6 is a cross-sectional view showing the monitoring window of an embodiment of the present invention. 7 are sectional views showing a monitoring window according to another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1...Metal ring, 1a...Inner peripheral surface, 2...Window glass, 2a...Jig contact surface (inner surface), 13...Transparent adhesive material, 14...Transparent plate.

Claims (1)

[Scope of Claim for Utility Model Registration] A glass disc is placed inside a metal ring placed on a sealing jig, and the glass disc is heated and melted to weld a transparent window glass inside the metal ring. , A transparent adhesive material is applied to the jig contact surface side of the transparent window glass to fill in minute irregularities on the jig contact surface, and a hardness greater than the hardness of the transparent adhesive material after curing is applied via the transparent adhesive material. A surveillance window characterized by adhesively forming a transparent plate having